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javalocaldate

How to compare if a set of LocalDate (holidays) contains a given MonthDay?

How do i exctract the monthDay in a LocalDate? I need to solve this within tomorrow so any help soon would be apreciated!

private final Set<MonthDay> recurringHolidays = new HashSet<>();
private final Set<LocalDate> holidays = new HashSet<>();


public void setHoliday(final LocalDate date) {
     holidays.add( date );
}

public void setHolidayIfIsRecurring() {

    for (LocalDate holidayLocalDate: getHolidays())
        for (MonthDay monthDay: getRecurringHolidays()){
            
            LocalDate monthdayToLocalDate = monthDay -------------????
            
            if (!setOfHolidays().contains( monthdayToLocalDate ) ){
                setHoliday( (monthDay) );
            }
        }
}
Solution

  • LocalDate → MonthDay

    You can use MonthDay#from(TemporalAccessor). For example:

    import java.time.LocalDate;
import java.time.MonthDay;

public class Main {

  public static void main(String[] args) {
    LocalDate date = LocalDate.of(2020, 6, 20);
    MonthDay md = MonthDay.from(date);
    System.out.println(md);
  }
}

    That will output:

    --6-20

    MonthDay → LocalDate

    The issue here is that MonthDay obviously only represents a month and day-of-month, whereas LocalDate additionally represents a year. You need to decide how to determine what year should be used. Once you know that then two options are:

    For example:

    import java.time.LocalDate;
import java.time.MonthDay;
import java.time.Year;

public class Main {

  public static void main(String[] args) {
    MonthDay md = MonthDay.of(6, 20);
    Year year = Year.of(2020);
    
    LocalDate date1 = md.atYear(year.getValue());
    LocalDate date2 = year.atMonthDay(md);

    System.out.println(date1);
    System.out.println(date2);
  }
}

    That will output:

    2020-06-20
2020-06-20